The present invention relates to a threading apparatus and a threading method in a textile machine. More specifically, the present invention relates to a threading apparatus and a threading method by which threading operation from a twisting device to a winding device can be done easily in a textile machine, such as a draw false-twist texturing machine.
In a false-twist texturing machine or a draw false-twist texturing machine, a yarn supplied from a supply package on a creel is fed by means of a first feed roller, while twists imparted by a twisting device disposed downstream and run back along the yarn are heat set by means of a first heater disposed between the first feed roller and the twisting device, and the yarn is cooled at a stabilizing zone locating downstream of the first heater and is detwisted at the twisting device, and then the yarn is fed by means of a second feed roller and is wounded. In many cases, leaving the second roller, the yarn passes through a second heater and, if desired, through a third feed roller, and it is fed to the winding device.
In such a false-twist texturing machine or a draw false-twist texturing machine, known is a textile machine comprising: a main frame provided with twisting devices and second heaters; a winding frame provided with winding devices facing and spacing from the main frame; and an operator""s aisle disposed between the main frame and the winding frame. The yarn leaving the second heater passes beneath the operator""s aisle and is fed to the winding device.
When such a construction as described above wherein an operator""s aisle is disposed between the main frame and the winding frame is used, a so called individual doffing mechanism by which doffing operation from the winding parts of the winding frame is done for individual spindles can be readily disposed, and thus, while the threading operation can be done at the side facing the operator""s aisle, the fully wound packages can be doffed from the side opposite to the operator""s aisle.
Further, when the first heater is a heater which can be heated to a high temperature higher than 400xc2x0 C., since the heater length of the first heater can be relatively shortened, the yarn passage in the heating zone can be brought into a condition like a straight line by the application of such a separate construction of the main frame and the winding frame, and run back of twists imparted by the twisting device can be done effectively, and thus, quality of the false-twist textured yarn which will be obtained can be good.
In addition, when the second heater is a heater which can be heated to a high temperature between 250 and 600xc2x0 C., all of the twisting device, the feed rollers, and the second heater can be disposed in such a region that they can be serviced by an operator standing at the operator""s aisle, and the winding devices on the winding frame can also be located in such a region that they can be serviced by an operator standing at the operator""s aisle, and thus, the operator can readily perform operations, such as a threading operation without using a step.
As described above, many advantages can be achieved by the arrangement wherein the main frame is provided with the twisting devices and second heaters, the winding frame is provided with the winding devices, and the operator""s aisle is disposed between the frames. However, the most serious problem inherent to this arrangement is that the operator has to bend for threading operation since the yarn from the main frame to the winding frame passes beneath the floor disposed at the operator""s aisle.
Taking the problem inherent to such a conventional apparatus into consideration, it is an object of the present invention to provide an apparatus and method for threading a yarn onto a textile machine, especially false-twist texturing machine or draw false-twist texturing machine, by which an operator can perform threading operation around the operator""s aisle without bending.
It is another object of the present invention to provide a threading apparatus by which threading operation onto a second heater heated at a temperature of between 250 and 600xc2x0 C. without encountering any substantial problems.
Further, it is a still other object of the present invention to provide a threading apparatus by which threading operation onto a winding device can be done very easily.
According to the present invention, the above-described objects are achieved by a yarn threading apparatus in a textile machine comprising:
a main frame provided with twisting devices and heaters disposed downstream of the twisting devices; and
a winding frame facing the main frame sandwiching an operator""s aisle therebetween and provided with winding devices, whereby a yarn leaving the heater disposed on the main frame is guided along the operator""s aisle to the winding device disposed on the winding frame, characterized in that
a yarn guide pipe is disposed extendably and retractably along the operator""s aisle,
a yarn feed roller device is so disposed that it locates at the yarn feeding position when the yarn guide is retracted and that it moves to a stand-by position when the guide pipe is extended, and
a yarn feed tube provided with a yarn feed nozzle is disposed between the extended end of the yarn guide pipe and the winding device.
Further, the present invention achieves the objects by a yarn threading apparatus in a textile machine comprising:
a main frame provided with twisting devices and heaters disposed downstream of the twisting devices; and
a winding frame facing the main frame sandwiching an operator""s aisle therebetween and provided with winding devices, whereby a yarn leaving the heater disposed on the main frame is guided beneath the operator""s aisle to the winding device disposed on the winding frame, characterized in that
the heater is provided with a yarn threading slit extending along a yarn passage, and
a guide member which is engageable with and disengageable from the yarn prior to being threaded into the heater is disposed adjacent to the yarn threading slit, whereby while the yarn is guided from the guide member to the winding device passing beneath the operator""s aisle, the yarn is disengaged from the guide member and is threaded into the heater through the yarn threading slit.
In this occasion, it is preferred that the guide member is a pipe with a spiral cross section which is disposed adjacent to the heater and which is provided with a yarn removing slit extending along the yarn passage.
Further, the present invention achieves the above-described objects by a yarn threading apparatus in a textile machine comprising:
a main frame provided with twisting devices and heaters disposed downstream of the twisting devices; and
a winding frame facing the main frame sandwiching an operator""s aisle therebetween and provided with winding devices, whereby a yarn leaving the heater disposed on the main frame is guided along the operator""s aisle to the winding device disposed on the winding frame,
characterized in that
the heater is provided with a yarn threading slit extending along a yarn passage,
a guide pipe member with a spiral cross section and provided with a yarn removing slit extending along the yarn passage is disposed adjacent to the yarn threading slit, and the member is engageable with and disengageable from the yarn prior to being threaded into the heater,
a yarn guide pipe is disposed extendably and retractably along the operator""s aisle,
a yarn feed roller device is so disposed that it locates at the yarn feeding position when the yarn guide is retracted and that it moves to a stand-by position when the guide pipe is extended, and
a yarn feed tube provided with a yarn feed nozzle is disposed between the extended end of the yarn guide pipe and the winding device.
In this occasion, it is preferred that the heater is a non-contact type high temperature heater which is capable of being heated at a temperature between 250 and 600xc2x0 C.
Further, the present invention provide a yarn threading apparatus in a textile machine comprising:
a winding device and a threading device disposed in front of the winding device, characterized in that the threading device comprising:
a yarn feed tube provided with a yarn feed nozzle;
a guide member extending between a front end of the yarn feed tube and a position in front of the winding device; and
a yarn guide bar locating between the guide member and the winding device and extending in a traversing direction of the winding device, and
the guide member is provided with:
a bottom surface which extends from the front end of the yarn feed tube and an end of which opposite to the yarn feed tube is smoothly curved toward the winding device over the guide bar; and
side walls projecting from both sides of the bottom surface towards the winding device.
The present invention may be a yarn threading apparatus in a textile machine comprising:
a main frame provided with twisting devices and heaters disposed downstream of the twisting devices, and threading devices disposed in front of the winding devices; and
a winding frame facing the main frame sandwiching an operator""s aisle therebetween and provided with winding devices, whereby a yarn leaving the heater disposed on the main frame is guided along the operator""s aisle to the winding device disposed on the winding frame,
characterized in that
the heater is provided with a yarn threading slit extending along a yarn passage,
a guide pipe member with a spiral cross section and provided with a yarn removing slit extending along the yarn passage is disposed adjacent to the yarn threading slit, and the member is engageable with and disengageable from the yarn prior to being threaded into the heater,
a yarn guide pipe is disposed extendably and retractably along the operator""s aisle,
a yarn feed roller device is so disposed that it locates at the yarn feeding position when the yarn guide pipe is retracted and that it moves to a stand-by position when the guide pipe is extended, and
a yarn feed tube provided with a yarn feed nozzle is disposed between the extended end of the yarn guide pipe and the winding device, and
the threading device comprises:
a yarn feed tube provided with a yarn feed nozzle;
a guide member extending between a front end of the yarn feed tube and a position in front of the winding device; and
a yarn guide bar locating between the guide member and the winding device and extending in a traversing direction of the winding device, and the guide member being provided with:
a bottom surface which extends from the front end of the yarn feed tube and an end of which opposite to the yarn feed tube is smoothly curved toward the winding device over the guide bar; and
side walls projecting from both sides of the bottom surface towards the winding device.
In this occasion, it is preferred that the height of the side walls of the guide member increases from the front end of the yarn feed tube to another end opposite to the yarn feed tube so that yarn feed air jetted from the front end of the yarn feed tube via the yarn feed nozzle diverges as it moves away from the yarn feed tube so as to smoothly transfer the yarn.
It is also preferred that the front end of the yarn feed tube locates at a fulcrum of traverse motion of the winding device so that the traverse motion of the yarn which has been threaded is not disturbed.
Further, it is preferred that a suction device is disposed between the guide bar and the winding device so as to ensure the threading operation.
The present invention may be a yarn threading apparatus in a textile machine comprising:
a main frame provided with twisting devices and yarn feed rollers disposed downstream of the twisting devices; and
a winding frame facing the main frame sandwiching an operator""s aisle therebetween and provided with winding devices, whereby a yarn travels beneath the operator""s aisle,
characterized in that
a guide pipe provided with a yarn feed nozzle is disposed along the operator""s aisle, and a yarn feed tube provided with a yarn nozzle is disposed between an end of the guide pipe near the winding frame to the winding device, so that the yarn from the main frame is threaded onto the winding device.
In this occasion, it is preferred that the main frame has heaters mounted below the feed rollers, the heater is provided with a yarn threading slit extending along a yarn passage, and a guide member which is engageable with and disengageable from the yarn prior to being threaded into the heater is disposed adjacent to the yarn threading slit, and the guide member is provided with a slit through which the yarn is disengaged from the guide member so as to be threaded into the heater.
Further, the present invention provides a method for threading a yarn on a textile machine comprising:
a main frame provided with twisting devices and heaters disposed downstream of the twisting devices; and
a winding frame facing the main frame sandwiching an operator""s aisle therebetween and provided with winding devices, whereby a yarn leaving the heater disposed on the main frame is guided along the operator""s aisle to the winding device disposed on the winding frame,
the heater is provided with a yarn threading slit extending along a yarn passage,
a guide pipe member having a spiral cross section and provided with a yarn removing slit extending along the yarn passage, which member is engageable with and disengageable from the yarn prior to being threaded into the heater is disposed adjacent to the yarn threading slit,
a yarn guide pipe is disposed extendably and retractably along the operator""s aisle,
a yarn feed roller device is so disposed that it locates at the yarn feeding position when the yarn guide is retracted and that it moves to a stand-by position when the guide pipe is extended, and
a yarn feed pipe provided with a yarn feed nozzle is disposed between the extended end of the yarn guide pipe and the winding device, characterized in that
a yarn end is positioned at the entrance of the guide pipe member, and
the yarn is guided by means of effect of the yarn feed nozzle from the guide pipe member to the winding device through the guide pipe,
then, the yarn is disengaged from the guide pipe member through the yarn removing slit, and
the thus disengaged yarn is threaded into the heater through the yarn threading slit.
It has been conventionally and partially done to thread a yarn into a heater formed in a completely tubular shape by means of a suction, for example, U.S. Pat. No. 3,999,360. However, when a yarn is threaded in such a heater with a completely tubular shape, if the threading operation is performed under the condition wherein the yarn is not forwarded while the heater is heated to a high temperature, yarn breakage occurs readily and threading operation fails. Accordingly, threading operation onto such a conventionally known heater having tubular shape can be carried out only when the temperature of the heater is relatively low.
Conventionally, a threading apparatus using suction has been known, for example French Patent Application Laid-open No. 2,695,631. However, such an apparatus has not been used to thread a yarn beneath the threading aisle formed between the main frame and the winding frame.